Data on opium addict-patients and treatment outcomes have been obtained from three sources in Laos: 1. In late 1972 Laos began a voluntary medical detoxification program for opium addicts. Data collected on 640 individuals included demographic characteristics, narcotic history, current narcotic usage, and several clinical variables. 2. Beginning in 1971 Laos -- in collaboration with Buddhist religious groups -- sent over 2,000 addicts for treatment to a temple in Thailand (Wat Than Kha Bok). This program consisted of "cold turkey" withdrawl, religious ceremonies, and a "synanon" approach to treatment. Demographic data, duration of opium addiction, and some clinical data were collected on 800 addicts from this program. 3. A follow-up study of addicts treated in both the above locations was made at one year post-treatment by the investigator. The survey sample was representative of addicts treated and entailed travel by the investigator to 12 villages in three separate provinces in Laos during 1974. The complexity and quantity of these data will require computer analysis due to the large number of subjects and variables. In addition, much of these data are now recorded in the Lao language and will require translation into English prior to coding and analysis. These patient-addicts will be compared to a sample of non-patient addicts from whom similar data were collected. In addition, this patient sample includes a group of American and European addicts who voluntarily sought treatment at the medical detoxification program in Vientiane, Laos, thus providing an opportunity to study expatriate "world traveler" addicts. And finally, a group of Asia heroin addict-patients in this sample provides an opportunity to study those individuals who abandon the traditional opium for heroin.